﻿<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
    <style>
        * {
            margin: 0;
            padding: 0;
            list-style: none;
        }

        .box {
            width: 90%;
            margin: 0 auto;
            overflow: hidden;
            position: relative;
        }

        ul {
            display: flex;
            position: relative;
            left: 0;
            transition: left .2s linear;
        }

        ol {
            display: flex;
            position: absolute;
            bottom: 10px;
            width: 100%;
            left: 0;
            justify-content: center;
        }

            ol > li {
                width: 10px;
                height: 10px;
                background-color: #fff;
                margin: 0 8px;
            }

                ol > li.action {
                    background-color: black;
                }

        img {
            border-radius: 5px;
            display: block;
        }

        .boximg {
            width: 90vw;
        }
    </style>
</head>
<body>
    <div class="box">
        <ul>
            <!-- <li>
                <img src="" alt="">
            </li> -->
        </ul>
        <ol>
            <!-- <li></li> -->
        </ol>
    </div>
    <script>
        var image = ["https://m15.360buyimg.com/mobilecms/s1062x420_jfs/t1/33428/39/16450/106681/6311cad7Ef9b3d856/f10720b7f8f38937.jpg!cr_1053x420_4_0!q70.jpg",
        "https://m15.360buyimg.com/mobilecms/jfs/t1/3230/40/20384/44107/62daf2d9E5c5e0e55/03ab360c40ddc266.jpg!cr_1125x449_0_166!q70.jpg",
        "https://m15.360buyimg.com/mobilecms/jfs/t1/110775/22/28940/94917/62e5bc6dE569b2244/5d14fc9f06d87341.jpg!cr_1125x449_0_166!q70.jpg"];

        var ul = document.querySelector(`.box>ul`);
        var ol = document.querySelector(`.box>ol`);
        var box = document.querySelector(`.box`);

        var str = ``, str1 = ``;
        for (var k = 0; k < image.length; k++) {
            str += `<li><img class="boximg" src="${image[k]}" alt=""></li>`;
            if (k==0) {
                str1 += `<li class="action"></li>`;
            } else {
                str1 += `<li></li>`;
            }
            
        }
        ul.innerHTML = str;
        ol.innerHTML = str1;
        ul.style.width = image.length * box.offsetwidth + `px`;

        var i = 0;
        var ollis = document.querySelectorAll(`.box>ol>li`);

        var start = 0;
        box.ontouchend = function (e) {
            start = parseInt(e.touches[0].clientX);
        }
        box.ontouchend = function (e) {
            var end = parseInt(e.changedTouches[0].clientX);
        }
        if (start>end&&start-end>=50) {
            i++;
            if (i == image.length) i = image.length - 1;
        } else if (end - start >= 50) {
            i--;
            if (i < 0) i = 0;
        }
        var l = i * -box.offsetWidth;
        ul.style.left = l + "px";
        for (var m = 0; m < ollis.length; m++) {
            ollis[m].classList.remove("action");
        }
        ollis[i].classList.add("action");
    </script>
</body>
</html>